With the continuous development of display technology, display devices are widely applied in the display field. The routine display device is generally a liquid crystal display (LCD).
The LCD generally adopts liquid crystal molecules to cooperate with a polarizer to achieve image display. The polarizer in the LCD includes an upper polarizer and a lower polarizer. The upper polarizer is disposed on a backlight side of an array substrate; the lower polarizer is disposed on a light-emitting side of a color filter (CF) substrate; and a backlight is disposed on one side of the upper polarizer away from the array substrate. When light emitted by the backlight transmits through the upper polarizer, component of which the vibration direction is the same as the polarization direction of the upper polarizer transmits through the upper polarizer, subsequently transmits through the array substrate, a liquid crystal layer and the color filter substrate, and arrives at the lower polarizer; light component arriving at the lower polarizer of which the vibration direction is the same as the polarization direction of the lower polarizer transmits through the lower polarizer and is finally exited from the lower polarizer. The routine polarizer is normally a wire grid polarizer which is formed by a plurality of parallel metal lines on a substrate by coining. The polarization direction of the wire grid polarizer is perpendicular to the lengthwise direction of the metal lines.